Weighing devices, such as retail scales, are used, for example, in supermarkets, delicatessens, etc., for weighing quantities of edible consumer products. These weighing devices typically include a printing unit for printing out paper receipts or labels having the weight, price, product type and the like. These receipts or labels exit through an opening of the printing unit for removal, for example, using a tearing blade. In order to maintain the hygienic standards necessary for such weighing devices, the weighing devices must be cleaned regularly. However, this regular cleaning, especially when done with less care and larger amounts of water or cleaning fluid, presents the risk that the water or cleaning fluid will infiltrate into the opening of the printing unit of the weighing device and thereby damage the printing unit and cause the printing unit or the entire weighing device to have to be replaced.
One method of making a housing waterproof is to have the housing fully enclose internal components to seal the internal components in the housing. However, printing units should advantageously include at least one opening, in contrast to an enclosed compartment, in order to deliver and provide easy and immediate access to printed substrates. For example, a retail scale will ordinarily print and deliver labels including a price, weight, product type, etc. For this purpose, therefore, the printing unit of a retail scale has at least one opening through which water can infiltrate. In addition to this at least one opening, further challenges to making a housing of a printer unit waterproof are presented by the fact that the interiors of printing units should be easily accessible for changing label rolls, service, maintenance, etc.